If smoother surfaces produce less friction than rough surfaces when rubbed together, what would happen if the rough surfaces weared down and became smooth?
Well, I figured. I guess I was focusing most on the material of the surfaces, and that confused me...
If rough surfaces wear down and become smooth, the amount of friction between them would decrease.
To understand why, we need to consider the microscopic irregularities on the surface of an object. When two rough surfaces come into contact and slide against each other, the raised portions of one surface get trapped in the corresponding depressions on the other surface. This creates more contact points and increases the friction between the two surfaces.
However, as the rough surfaces wear down through repetitive rubbing or natural erosion, the high points get flattened, and the overall surface becomes smoother. With smoother surfaces, there are fewer contact points between the two surfaces, reducing the frictional forces at play.
So, if rough surfaces wear down and become smooth, the friction between them will diminish, making it easier for the objects to move against each other. This is why polished or lubricated surfaces tend to have less friction than rough surfaces, as they minimize interlocking irregularities and allow for smooth sliding.
Hmmm ... let's see ...
smoother surfaces produce less friction
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